1. Field of the Invention
The subject invention pertains to therapeutic equipment useful to support a patient during ambulation therapy, wherein the patient provides force for movement of the support apparatus. More particularly, this invention relates to such support apparatus which operate only as stabilizing means to prevent fall or loss of balance to a patient attempting to walk on his own strength.
2. Prior Art
Various types of therapy devices have been developed to assist patients in strengthening muscle tone and coordination required to walk without assistance of crutches or other support means. Until such strength and balance is developed, the patient must be assisted by a physical therapist or some form of apparatus which supports the patient in upright position and prevents fall due to loss of balance or physiological weakness. Two basic classes of devices have emerged which are distinguished by the use or absence of a propelled carriage.
U.S. Pat. Nos. 3,780,663 and 3,985,082 disclose two types of propelled devices used to regulate a patient's walking speed, while supporting the patient in a standing position.
Although the apparatus of these disclosurers is useful in certain applied fields of therapy, several disadvantages remain. Of primary concern is the constant requirement for regulation of speed in accordance with the capacity of the patient under therapy. Frequently, such patients are unable to pace themselves and therefore they require the assistance of a physical therapist. Furthermore, variation of speed by the patient is limited due to the fixed drive movement associated with such devices. In other words, the patient is not free to move at his own pace, but is carried by the machine in accordance with a preset speed. The consequence is a lack of sense of accomplishment inasmuch as the machine is primarily the cause of forward movement. In addition, the excessive cost of such apparatus usually precludes installation within a home or other temporary location of therapy. Also, the inventor herein has noted a strong reluctance for small children to be comfortable with such power-driven units whose complexity tends to create fear and distrust within the inexperienced child.
A third embodiment of power-driven orthopedic devices is disclosed in U.S. Pat. No. 2,871,915. This device comprises a continuous chain as opposed to the use of rollers on a track, as developed in the previous two references. The latter patent includes disclosure of a frame to stabilize the patient in upright position during ambulation therapy. Here again, there is little flexibility of movement for the patient under therapy, in view of the regulated speed imposed by the power-driven apparatus. In addition, the noise is often disconcerting to a young child as is the associated complex structure. These psychological influences may be quite serious where the child is of limited mental capacity. These factors may combine to discourage the regular use of such therapeutic equipment, or at least build strong resistance within the child toward cooperation.
Under such circumstances a preferred therapeutic apparatus would be without a power source and associated propulsion hardware. A form of this class of device is disclosed in U.S. Pat. No. 2,478,004. The structure of this apparatus consists basically of a horizontal cylindrical track which carries a single roller assembly along its length. The roller is grooved to track along the cylindrical rail in response to force supplied by the patient during therapy. The disclosed structure provides the simplicity and portability for use with retarded children; however, it fails to provide a smooth motion which helps to assist the patient in developing rhythm and coordination.
Because of its structure, the subject apparatus tends to jump or lunge in an irregular fashion, tending to disrupt the balance and relaxed composure of the patient. This irregular forward motion is further coupled with side-to-side motion resulting from rotation of the roller and carrier about the longitudinal axis of the cylindrical track.
Furthermore, each of the aforementioned patents provides frame or harness structure which is somewhat problematic. None of the harnesses will provide rigid support to the upper torso of the patient when the apparatus has any substantial slack. Such slack may be, at times, desirable to give full opportunity to the patient to walk somewhat independently of the apparatus, such apparatus being present only to support the patient in the event of fall or loss of balance. With retarded children, the problem of imbalance encourages additional fears against using such equipment on a regular basis. Without the security of upright support, the patient must be conscious of upper torso muscular control, as well as the complex muscle regulation required to walk. In early stages of ambulation therapy, it may be preferable to relieve the patient of concern for balance and muscular coordination for his upper torso, freeing his attention to concentrate on leg movement.